Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262106AbUC1G5F (ORCPT ); Sun, 28 Mar 2004 01:57:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262108AbUC1G5E (ORCPT ); Sun, 28 Mar 2004 01:57:04 -0500 Received: from smtp100.mail.sc5.yahoo.com ([216.136.174.138]:14249 "HELO smtp100.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S262106AbUC1G5A (ORCPT ); Sun, 28 Mar 2004 01:57:00 -0500 Message-ID: <40667734.8090203@yahoo.com.au> Date: Sun, 28 Mar 2004 16:56:52 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040122 Debian/1.6-1 X-Accept-Language: en MIME-Version: 1.0 To: "Eric D. Mudama" CC: Jeff Garzik , linux-ide@vger.kernel.org, Linux Kernel , Andrew Morton Subject: Re: [PATCH] speed up SATA References: <4066021A.20308@pobox.com> <40661049.1050004@yahoo.com.au> <20040328044029.GB1984@bounceswoosh.org> In-Reply-To: <20040328044029.GB1984@bounceswoosh.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 823 Lines: 22 Eric D. Mudama wrote: > On Sun, Mar 28 at 9:37, Nick Piggin wrote: > >> I think 32MB is too much. You incur latency and lose >> scheduling grainularity. I bet returns start diminishing >> pretty quickly after 1MB or so. > > > 32-MB requests are the best for raw throughput. > > ~15ms to land at your target location, then pure 50-60MB/sec for the .5 > seconds it takes to finish the operation. (media limited at that point) > > Sure, there's more latency, but I guess that is application dependant. > What about a queue depth of 2, and writing that 32MB in 1MB requests? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/